dotnet/wpf · error · ArgumentException

' ' is not a valid value for ' '.

Error message

'{1}' is not a valid value for '{0}'.

What it means

The ILockBytes Stat implementation validates grfStatFlag, allowing only the STATFLAG_NONAME and STATFLAG_NOOPEN bits. Any other flag bit set causes ArgumentException (InvalidArgumentValue) because the wrapper does not support the full native STATSTG flag surface.

Solutions

1. Pass only 0, STATFLAG_NONAME (1), STATFLAG_NOOPEN (2), or their combination.
2. Mask the flag with (grfStatFlag & ~(STATFLAG_NONAME | STATFLAG_NOOPEN)) and reject before calling.
3. Catch ArgumentException and inspect grfStatFlag.ToString() in the message to identify the bad value.

Example fix

// before
lockBytes.Stat(0x10, out statstg); // unsupported flag
// after
const int STATFLAG_NONAME = 1;
lockBytes.Stat(STATFLAG_NONAME, out statstg);

const int STATFLAG_NONAME = 0x1, STATFLAG_NOOPEN = 0x2;
if ((grfStatFlag & ~(STATFLAG_NONAME | STATFLAG_NOOPEN)) != 0)
    throw new ArgumentException(nameof(grfStatFlag), "only STATFLAG_NONAME/STATFLAG_NOOPEN are supported");

try { lockBytes.Stat(grfStatFlag, out statstg); }
catch (ArgumentException ex) { /* grfStatFlag contained unsupported bits */ }

When it happens

Trigger: Calling IStream/ILockBytes Stat with grfStatFlag containing bits outside STATFLAG_NONAME (0x1) and STATFLAG_NOOPEN (0x2) — e.g. passing an undocumented value or a garbage/shifted flag.

Common situations: Porting native COM code that passes flags this managed wrapper doesn't support, or forwarding a value from another API whose flag enum has different bit meanings.

Understand the failure class

Background: "unknown output mode", "invalid value for flag", "expects true/false": fixing invalid flag value errors in CLI tools — this error's family across 24 libraries.

Related errors

• 0x80040206
• 0x80040207
• ' ' is not a valid value for ' '.
• A read or write operation references a location outside the…
• ArgumentException(message, name)

AI-assisted analysis of dotnet/wpf@81131a70a4 (2026-09-14). Data as JSON: /api/errors/dad4907ab641026f. Report an issue: GitHub.

Appendix: source

Thrown at src/Microsoft.DotNet.Wpf/src/WindowsBase/MS/Internal/IO/Packaging/CompoundFile/PrivateUnsafeNativeCompoundFileMethods.cs:178

                UInt64 libOffset,
                UInt64 cb,
                int dwLockType )
            {
                throw new NotSupportedException();
            }


            void UnsafeNativeILockBytes.Stat(
                out System.Runtime.InteropServices.ComTypes.STATSTG pstatstg,
                int grfStatFlag )
            {
                CheckDisposed();

                if ((grfStatFlag & ~(SafeNativeCompoundFileConstants.STATFLAG_NONAME | 
                                     SafeNativeCompoundFileConstants.STATFLAG_NOOPEN  )) != 0)
                {
                    // validate grfStatFlag's value
                    throw new ArgumentException(SR.Format(SR.InvalidArgumentValue, "grfStatFlag", grfStatFlag.ToString(CultureInfo.InvariantCulture)));
                }

                System.Runtime.InteropServices.ComTypes.STATSTG returnValue = new System.Runtime.InteropServices.ComTypes.STATSTG
                {
                    grfLocksSupported = 0, // No lock supported

                    cbSize = _baseStream.Length,
                    type = SafeNativeCompoundFileConstants.STGTY_LOCKBYTES
                };

                pstatstg = returnValue;
            }

            private Stream _baseStream;
        }

        /////////////////////////////////////////////////////
        // Security Suppressed Private Interfaces

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